Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297938
K. Lindberg, C. Jensen
Wiki systems form a subclass of the more general Open Collaborative Authoring Systems, where content is created and maintained by a user community. The ability of anyone to edit the content is, at the same time, their strength and their weakness. Anyone can write documents that improve the value of the wiki-system, but at the same time, anyone can also introduce errors into these documents, by accident or on purpose. A security model for wiki-style authoring systems has previously been proposed. This model is based on both static and dynamic document access controls that enforce a simple integrity based security policy. In this paper, we present a new policy for the existing wiki security model, which provides a higher degree of parameterization and adaptability. The new policy is analyzed and compared to the original policy. Our evaluation shows that this new policy provides stronger security when the number of malicious and colluding users is low, but it has a clearly defined level of tolerance in terms of the amount of work required by an attacker to achieve a given probability of violating the policy. Efforts beyond that level, can allow such users to take control of the system, but this is true for all soft security systems. We show that the system parameters can be tuned so that the amount of work required by malicious and colluding users to reach this level is well beyond most attackers' capabilities.
{"title":"Collaborative trust evaluation for wiki security","authors":"K. Lindberg, C. Jensen","doi":"10.1109/PST.2012.6297938","DOIUrl":"https://doi.org/10.1109/PST.2012.6297938","url":null,"abstract":"Wiki systems form a subclass of the more general Open Collaborative Authoring Systems, where content is created and maintained by a user community. The ability of anyone to edit the content is, at the same time, their strength and their weakness. Anyone can write documents that improve the value of the wiki-system, but at the same time, anyone can also introduce errors into these documents, by accident or on purpose. A security model for wiki-style authoring systems has previously been proposed. This model is based on both static and dynamic document access controls that enforce a simple integrity based security policy. In this paper, we present a new policy for the existing wiki security model, which provides a higher degree of parameterization and adaptability. The new policy is analyzed and compared to the original policy. Our evaluation shows that this new policy provides stronger security when the number of malicious and colluding users is low, but it has a clearly defined level of tolerance in terms of the amount of work required by an attacker to achieve a given probability of violating the policy. Efforts beyond that level, can allow such users to take control of the system, but this is true for all soft security systems. We show that the system parameters can be tuned so that the amount of work required by malicious and colluding users to reach this level is well beyond most attackers' capabilities.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126176834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297919
F. Buccafurri, Lidia Fotia, G. Lax
In new generation social networks, we expect that the demand of tools allowing the user to effectively control privacy, without relying on the provider trustworthiness, will be more and more increasing. A lot of precious information is currently released by users with no privacy control whenever they evaluate resources, which, for example, is done in Facebook through the “Like Button”. A mechanism allowing the user to express her preferences fully preserving her privacy is thus desired, especially if it is able to protect user privacy also in case of untrustworthy social network provider. In this paper, we propose a solution to this problem, based on a DHT-based P2P social network and on a cryptographic protocol relying on partially blind digital signatures. The protocol is shown to be a solution to the trade-off between feasibility and security, since it guarantees the needed security requirements without including the complex features of existing e-voting systems.
{"title":"Privacy-preserving resource evaluation in social networks","authors":"F. Buccafurri, Lidia Fotia, G. Lax","doi":"10.1109/PST.2012.6297919","DOIUrl":"https://doi.org/10.1109/PST.2012.6297919","url":null,"abstract":"In new generation social networks, we expect that the demand of tools allowing the user to effectively control privacy, without relying on the provider trustworthiness, will be more and more increasing. A lot of precious information is currently released by users with no privacy control whenever they evaluate resources, which, for example, is done in Facebook through the “Like Button”. A mechanism allowing the user to express her preferences fully preserving her privacy is thus desired, especially if it is able to protect user privacy also in case of untrustworthy social network provider. In this paper, we propose a solution to this problem, based on a DHT-based P2P social network and on a cryptographic protocol relying on partially blind digital signatures. The protocol is shown to be a solution to the trade-off between feasibility and security, since it guarantees the needed security requirements without including the complex features of existing e-voting systems.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116390133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297950
C. Jensen
Summary form only given. Traditional security technologies are based on numerous assumptions about the environment in which systems are used. This includes assumptions about the enforcement of legislative and contractual frameworks, limitations of particular technologies and the constraints on human behaviour imposed by social and religious norms. Most of these assumptions, however, are implicit and they will fail when the environment of the systems change, e.g., when systems are used on a global scale on the Internet. This talk identifies such implicit assumptions in current security technologies and show how many of them concern the placement of trust on human or system agents. We argue that making such assumptions about trust explicit is an essential requirement for the future of system security and argue why the formalisation of computational trust is necessary when we wish to reason about system security.
{"title":"The role of trust in computer security","authors":"C. Jensen","doi":"10.1109/PST.2012.6297950","DOIUrl":"https://doi.org/10.1109/PST.2012.6297950","url":null,"abstract":"Summary form only given. Traditional security technologies are based on numerous assumptions about the environment in which systems are used. This includes assumptions about the enforcement of legislative and contractual frameworks, limitations of particular technologies and the constraints on human behaviour imposed by social and religious norms. Most of these assumptions, however, are implicit and they will fail when the environment of the systems change, e.g., when systems are used on a global scale on the Internet. This talk identifies such implicit assumptions in current security technologies and show how many of them concern the placement of trust on human or system agents. We argue that making such assumptions about trust explicit is an essential requirement for the future of system security and argue why the formalisation of computational trust is necessary when we wish to reason about system security.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124111252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297934
C. Buntain, J. Golbeck, Dana S. Nau, Sarit Kraus
This work provides a game theoretic framework through which one can study the different trust and mitigation strategies a decision maker can employ when soliciting advice or input from a potentially self-interested third-party. The framework supports a single decision maker's interacting with an arbitrary number of either honest or malicious (and malicious in varying ways) advisors. We include some preliminary results on the analysis of this framework in some constrained instances and propose several avenues of future work.
{"title":"Advice and trust in games of choice","authors":"C. Buntain, J. Golbeck, Dana S. Nau, Sarit Kraus","doi":"10.1109/PST.2012.6297934","DOIUrl":"https://doi.org/10.1109/PST.2012.6297934","url":null,"abstract":"This work provides a game theoretic framework through which one can study the different trust and mitigation strategies a decision maker can employ when soliciting advice or input from a potentially self-interested third-party. The framework supports a single decision maker's interacting with an arbitrary number of either honest or malicious (and malicious in varying ways) advisors. We include some preliminary results on the analysis of this framework in some constrained instances and propose several avenues of future work.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116943979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297952
Graeme Smith, J. Sanders
Self-organising systems have become important relatively recently. It is frequently claimed that their complex nature necessitates new formalisms to express and reason about them. In this paper the opposite view is taken. Following Back's use of action systems to express a distributed system as an initialised possibly nonterminating loop, here two simple but representative case studies of self-organising systems are explored using only conventional techniques. The first deals with the configuration of an ad hoc network and shows how safety and liveness can be accurately expressed with an initialised loop. The second involves, like many self-organising systems, probabilistic behaviour and it is shown that existing techniques suffice to establish the system behaviour. In conclusion, the techniques illustrated can be used to provide a higher level of assurance than is possible with simulation alone.
{"title":"Using conventional reasoning techniques for self-organising systems","authors":"Graeme Smith, J. Sanders","doi":"10.1109/PST.2012.6297952","DOIUrl":"https://doi.org/10.1109/PST.2012.6297952","url":null,"abstract":"Self-organising systems have become important relatively recently. It is frequently claimed that their complex nature necessitates new formalisms to express and reason about them. In this paper the opposite view is taken. Following Back's use of action systems to express a distributed system as an initialised possibly nonterminating loop, here two simple but representative case studies of self-organising systems are explored using only conventional techniques. The first deals with the configuration of an ad hoc network and shows how safety and liveness can be accurately expressed with an initialised loop. The second involves, like many self-organising systems, probabilistic behaviour and it is shown that existing techniques suffice to establish the system behaviour. In conclusion, the techniques illustrated can be used to provide a higher level of assurance than is possible with simulation alone.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123153326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297948
J. Bringer, H. Chabanne, Olivier Cipiere
In 2009, Shamir proposed the setbase approach to protect the privacy of biometric data during ID documents issuance. One year later, Bringer and Chabanne introduced negative databases for biometric data. In this paper, we show that negative database techniques can also be applied to the setbase approach to enforce some of its security characteristics.
{"title":"Combining the setbase approach with negative databases","authors":"J. Bringer, H. Chabanne, Olivier Cipiere","doi":"10.1109/PST.2012.6297948","DOIUrl":"https://doi.org/10.1109/PST.2012.6297948","url":null,"abstract":"In 2009, Shamir proposed the setbase approach to protect the privacy of biometric data during ID documents issuance. One year later, Bringer and Chabanne introduced negative databases for biometric data. In this paper, we show that negative database techniques can also be applied to the setbase approach to enforce some of its security characteristics.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122286129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297935
Mark Vinkovits
Research in the field of Trust Management is blooming producing new Trust Frameworks within short time intervals. However, trust researchers do not develop distributed systems. Most developers are not familiar with security procedures and therefore often introduce other security vulnerabilities during implementation. We wish to provide a solution for system designers and developers for applying Trust Management. As a first step of our work we investigated how our users understand the application of trust and reputation in distributed systems. During focus group workshops we collected a set of initial requirements. We learnt that users are familiar with the benefits gained by Trust Management but had not enough knowledge about its application.
{"title":"Towards requirements for trust management","authors":"Mark Vinkovits","doi":"10.1109/PST.2012.6297935","DOIUrl":"https://doi.org/10.1109/PST.2012.6297935","url":null,"abstract":"Research in the field of Trust Management is blooming producing new Trust Frameworks within short time intervals. However, trust researchers do not develop distributed systems. Most developers are not familiar with security procedures and therefore often introduce other security vulnerabilities during implementation. We wish to provide a solution for system designers and developers for applying Trust Management. As a first step of our work we investigated how our users understand the application of trust and reputation in distributed systems. During focus group workshops we collected a set of initial requirements. We learnt that users are familiar with the benefits gained by Trust Management but had not enough knowledge about its application.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"354 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115890896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297925
Shushan Zhao, R. Kent, A. Aggarwal
Key management (KM) and secure routing (SR) are two most important issues for Mobile Ad-hoc Networks (MANETs), but previous solutions tend to consider them separately. This leads to KM-SR interdependency cycle problem. In this paper, we propose an integrated KM-SR scheme that addresses KM-SR interdependency cycle problem. By using identity based cryptography (IBC), this scheme provides security features including confidentiality, integrity, authentication, freshness, and non-repudiation. Compared to symmetric cryptography, traditional asymmetric cryptography and previous IBC schemes, this scheme has improvements in many aspects. We provide theoretical proof of the security of the scheme and demonstrate the efficiency of the scheme with practical simulation.
{"title":"An integrated key management and secure routing framework for Mobile Ad-Hoc Networks","authors":"Shushan Zhao, R. Kent, A. Aggarwal","doi":"10.1109/PST.2012.6297925","DOIUrl":"https://doi.org/10.1109/PST.2012.6297925","url":null,"abstract":"Key management (KM) and secure routing (SR) are two most important issues for Mobile Ad-hoc Networks (MANETs), but previous solutions tend to consider them separately. This leads to KM-SR interdependency cycle problem. In this paper, we propose an integrated KM-SR scheme that addresses KM-SR interdependency cycle problem. By using identity based cryptography (IBC), this scheme provides security features including confidentiality, integrity, authentication, freshness, and non-repudiation. Compared to symmetric cryptography, traditional asymmetric cryptography and previous IBC schemes, this scheme has improvements in many aspects. We provide theoretical proof of the security of the scheme and demonstrate the efficiency of the scheme with practical simulation.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"170 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131142004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297916
Arun Prakash, K. krishnan, B. Sy
We present a two-party secure information processing protocol referred to as SIPPA-2.0 - targeted towards privacy preserving biometric data comparison and reconstruction. The original intention of SIPPA as reported previously is to enable private data comparison and reconstruction between a client and a server when (a) the client possesses some data that are “sufficiently similar” to that of the server, and (b) the server provides a scalar helper data to facilitate private data reconstruction by the client. In SIPPA-2.0, private data comparison and reconstruction are based on new theoretical results and a novel secure computation protocol referred to as SLSSP. These new results allow us to design and develop the much improved SIPPA and SLSSP protocols guaranteeing (a) security under semi-malicious model rather than just semi-honest model, and (b) privacy assurance with arbitrary reconstruction accuracy controllable by the server. Security analysis proving SLSSP secure under the semi-honest and semi-malicious models is presented. SIPPA-2.0 is applied to enable privacy preserving fingerprint comparison; where two parties can compare their fingerprint samples and can obtain a similarity score without revealing their raw fingerprint to each other. Experimental results on the accuracy of fingerprint matching and the run-time performance are also reported.
{"title":"SIPPA-2.0 - Secure information processing with privacy assurance (version 2.0)","authors":"Arun Prakash, K. krishnan, B. Sy","doi":"10.1109/PST.2012.6297916","DOIUrl":"https://doi.org/10.1109/PST.2012.6297916","url":null,"abstract":"We present a two-party secure information processing protocol referred to as SIPPA-2.0 - targeted towards privacy preserving biometric data comparison and reconstruction. The original intention of SIPPA as reported previously is to enable private data comparison and reconstruction between a client and a server when (a) the client possesses some data that are “sufficiently similar” to that of the server, and (b) the server provides a scalar helper data to facilitate private data reconstruction by the client. In SIPPA-2.0, private data comparison and reconstruction are based on new theoretical results and a novel secure computation protocol referred to as SLSSP. These new results allow us to design and develop the much improved SIPPA and SLSSP protocols guaranteeing (a) security under semi-malicious model rather than just semi-honest model, and (b) privacy assurance with arbitrary reconstruction accuracy controllable by the server. Security analysis proving SLSSP secure under the semi-honest and semi-malicious models is presented. SIPPA-2.0 is applied to enable privacy preserving fingerprint comparison; where two parties can compare their fingerprint samples and can obtain a similarity score without revealing their raw fingerprint to each other. Experimental results on the accuracy of fingerprint matching and the run-time performance are also reported.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116768644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-07-16DOI: 10.1109/PST.2012.6297915
M. Harbach, S. Fahl, Michael Brenner, T. Muders, Matthew Smith
The growing adoption of cloud technology in sensitive application domains, such as medicine, gives rise to new problems in maintaining the privacy of the involved parties during authorisation. In such domains, an honest but curious service provider can derive sensitive information purely from the authorisation process. In this paper, we present a detailed discussion of this rising problem including a concrete example and argue the need for the combination of hidden credentials, hidden policies and hidden decisions. We then show that mechanisms explored in previous work only cover individual aspects of this problem, but do not achieve a comprehensive solution without making restrictive assumptions on the resources, policies or subjects to be protected. As a first step towards solving this problem, we introduce an abstract foundation for using homomorphic cryptography to provide the required combination of privacy as a wrapper for other access control (AC) mechanisms. We achieve hidden policies, hidden credentials and even hidden access control decisions, so that the subject of an AC request only learns whether or not access was granted. Meanwhile, the provider of a resource learns nothing at the policy decision point and only access frequencies for individual resources at the policy enforcement point. We postulate that this is the maximum achievable level of protection in the authorisation process, without making restrictive assumptions on the resources, policies or subjects to be protected. Once homomorphic cryptography achieves satisfactory performance, our model can be used to transparently add this protection to other access control models.
{"title":"Towards privacy-preserving access control with hidden policies, hidden credentials and hidden decisions","authors":"M. Harbach, S. Fahl, Michael Brenner, T. Muders, Matthew Smith","doi":"10.1109/PST.2012.6297915","DOIUrl":"https://doi.org/10.1109/PST.2012.6297915","url":null,"abstract":"The growing adoption of cloud technology in sensitive application domains, such as medicine, gives rise to new problems in maintaining the privacy of the involved parties during authorisation. In such domains, an honest but curious service provider can derive sensitive information purely from the authorisation process. In this paper, we present a detailed discussion of this rising problem including a concrete example and argue the need for the combination of hidden credentials, hidden policies and hidden decisions. We then show that mechanisms explored in previous work only cover individual aspects of this problem, but do not achieve a comprehensive solution without making restrictive assumptions on the resources, policies or subjects to be protected. As a first step towards solving this problem, we introduce an abstract foundation for using homomorphic cryptography to provide the required combination of privacy as a wrapper for other access control (AC) mechanisms. We achieve hidden policies, hidden credentials and even hidden access control decisions, so that the subject of an AC request only learns whether or not access was granted. Meanwhile, the provider of a resource learns nothing at the policy decision point and only access frequencies for individual resources at the policy enforcement point. We postulate that this is the maximum achievable level of protection in the authorisation process, without making restrictive assumptions on the resources, policies or subjects to be protected. Once homomorphic cryptography achieves satisfactory performance, our model can be used to transparently add this protection to other access control models.","PeriodicalId":434948,"journal":{"name":"2012 Tenth Annual International Conference on Privacy, Security and Trust","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125330983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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